An arbitrator was called in to mediate a new contract between police and the city Friday night. The arbitrator ruled that patrol officers should get a 25.4 percent pay hike in the next six years.

According to Mayor Thomas M. Menino, the increase would cost city taxpayers an estimated $80 million. He said the contract would set an "unsustainable precedent" and doom future contract talks.

"My obligation as mayor is to make sure the city works financially, and even as I prepare to leave office, I have that responsibility and I have that responsibility until I leave," Menino said.

The mayor said he was urging the city council to veto the increase.

"This contract is too expensive for the city at this time," Menino said.

Mayoral candidate and State Representative Martin J. Walsh also criticized the ruling, saying it should have never reached the point of arbitration.

"It should not have gone to arbitration. It should have been dealt with six years ago when the contract expired. It should not have gone this far," Walsh said.

The award must be approved by the Boston City Council. If it is not, both sides go back to the bargaining table.

The other mayoral candidate, city councilor John R. Connolly, said Saturday on the steps of the State House that he would be deciding how to vote after meeting with both sides.

"I want to make an informed decision. I not going to make it based on what I read in the newspaper. I’m going to sit with the city and the CFO tomorrow. I’m going to sit with the Patrolmen’s Association on Monday and then I’ll make a decision quickly and in an informed manner," Connolly said.